By comparison it barely applies at all.
You don't think studying the actual history of the last time this country had a civil spasm along similar ideological lines might not yield some _more applicable_ lessons?
If you want a more recent conflict, try the Troubles in Northern Ireland.
The fascism analogy is chosen because it has huge emotional valence. It's not chosen for analytical reasons.
It can activate your feelings; it can't teach you very much.
